Biodegradable Profile Extruded Articles

Abstract

Biodegradable articles such as tubing and food service items are disclosed. The articles are extrusion molded from a polymer resin which is made up of at least 25 weight percent of at least one biodegradable polymer, such as polyhydroxyalkanoates. Preferably the articles are formed by profile extrusion.

What is claimed is: 
     
         1 . A biodegradable tubular article, wherein the tubular article is profile extrusion molded from a polymer resin comprising at least 25 weight percent of at least one biodegradable polymer. 
     
     
         2 . The biodegradable tubular article of  claim 1 , wherein the tubular article is selected from the group consisting of medical tubing, gas tubing, laboratory tubing, automotive tubing, drinking straws, and beverage stirrers. 
     
     
         3 . The biodegradable tubular article of  claim 1 , wherein the polymer resin comprises at least one biodegradable polymer selected from the group consisting of polyhydroxyalkanoates, polycaprolactone, polylactic acid, polybutylene succinate, polybutylene succinate-co-butylene adipate, polybutylene adipate terephthalate, blends of two or more of the aforementioned polymers, and reaction products of two or more of the aforementioned polymers. 
     
     
         4 . The biodegradable tubular article of  claim 1 , wherein the at least one biodegradable polymer comprises polyhydroxyalkanoates, and the polyhydroxyalkanoates comprise from about 65 to about 99.5 mole percent hydroxybutyrate moieties and from about 0.5 to about 35 mole percent hydroxyhexanoate moieties. 
     
     
         5 . The biodegradable tubular article of  claim 1 , wherein the at least one biodegradable polymer comprises polyhydroxyalkanoates having a weight average molecular weight from about 100,00 Daltons to about 7.5 million Daltons. 
     
     
         6 . The biodegradable tubular article of  claim 1 , wherein the at least one biodegradable polymer comprises a reaction product formed from reactive extrusion of polyhydroxyalkanoates and a second biodegradable polymer. 
     
     
         7 . The biodegradable tubular article of  claim 1 , wherein the at least one biodegradable polymer comprises polycaprolactone and/or polylactic acid having a weight average molecular weight from about 10,000 Daltons to about 300,000 Daltons. 
     
     
         8 . The biodegradable tubular article of  claim 1 , wherein the polymer resin comprises at least one biodegradable polymer selected from the group consisting polylactic acid, polybutylene succinate, polybutylene succinate adipate, polybutylene adipate terephthalate, and mixtures thereof. 
     
     
         9 . The biodegradable tubular article of  claim 1 , wherein the polymer resin further comprises from about 1 to about 50 weight percent of at least one filler selected from the group consisting of clays, calcium carbonate, talc, kaolinite, montomorillonite, bentonite, silica, chitin, titanium dioxide, nano clay, nanocellulose, mica and mixtures thereof. 
     
     
         10 . The biodegradable tubular article of  claim 1 , wherein the polymer resin further comprises from about 0.01 to about 20 weight percent of at least one nucleating agent selected from the group consisting of polyester waxes, behenamide, crodamide, stearamide, erucamide, pentaerythritol, sulfur, dipentaerythritol and mixtures thereof. 
     
     
         11 . The biodegradable tubular article of  claim 1 , wherein the polymer resin further comprises from about 1.0 to about 25 weight percent of at least one polysaccharide. 
     
     
         12 . The biodegradable tubular article of  claim 1 , wherein the polymer resin further comprises from about 0.5 to about 15 weight percent of at least one plasticizer selected from the group consisting of sebacates, citrates, fatty esters of adipic acid, fatty esters of succinic acid, fatty esters of glucaric acid, lactates, alkyl diesters, alkyl methyl esters, dibenzoates, propylene carbonate, caprolactone diols having a weight average molecular weight from about 200 to about 10,000 g/mol, polyethylene glycols having a weight average molecular weight from about 400 to about 10,000 g/mol, esters of vegetable oils, long chain alkyl acids, adipates, glycerol, isosorbide derivatives, and mixtures thereof. 
     
     
         13 . The biodegradable tubular article of  claim 1 , wherein the polymer resin further comprises from about 15 to about 35 weight percent of at least one filler, from about 1.0 to about 5.0 weight percent of at least one nucleating agent, and from about 0.01 to about 2 of at least one polymerization catalyst or initiator. 
     
     
         14 . A method for making a biodegradable tubular article, the method comprising the steps of:
 providing a polymer resin comprising at least 25 weight percent of at least one biodegradable polymer;   heating a charge of the polymer resin, in an extruder, to a temperature at or above the melting point of the polymer resin; and   profile extruding the polymer resin charge through a die to form a tubular article.   
     
     
         15 . The method of  claim 14 , wherein the tubular article is selected from the group consisting of medical tubing, gas tubing, laboratory tubing, automotive tubing, drinking straws, and beverage stirrers. 
     
     
         16 . The method of  claim 14 , wherein the polymer resin comprises at least one biodegradable polymer selected from the group consisting of polyhydroxyalkanoates, polycaprolactone, polylactic acid, polybutylene succinate, polybutylene succinate-co-butylene adipate, polybutylene adipate terephthalate, blends of two or more of the aforementioned polymers, and reaction products of two or more of the aforementioned polymers. 
     
     
         17 . The method of  claim 14 , wherein the at least one biodegradable polymer comprises polyhydroxyalkanoates, and the polyhydroxyalkanoates comprise from about 65 to about 99.5 mole percent hydroxybutyrate moieties and from about 0.5 to about 35 mole percent hydroxyhexanoate moieties. 
     
     
         18 . The method of  claim 14 , wherein the at least one biodegradable polymer comprises polyhydroxyalkanoates having a weight average molecular weight from about 10,000 Daltons to about 7.5 million Daltons. 
     
     
         19 . The method of  claim 14 , wherein the at least one biodegradable polymer in the polymer resin charge comprises a reaction product formed from reactive extrusion of polyhydroxyalkanoates and a second biodegradable polymer. 
     
     
         20 . The method of  claim 14 , wherein the at least one biodegradable polymer comprises polycaprolactone and/or polylactic acid having a weight average molecular weight from about 10,000 Daltons to about 300,000 Daltons. 
     
     
         21 . The method of  claim 14 , wherein the polymer resin comprises at least one biodegradable polymer selected from the group consisting polylactic acid, polybutylene succinate, polybutylene succinate-co-butylene adipate, polybutylene adipate terephthalate, and mixtures thereof. 
     
     
         22 . The method of  claim 14 , wherein the polymer resin further comprises from about 1 to about 50 weight percent of at least one filler selected from the group consisting of clays, calcium carbonate, talc, kaolinite, montmorillonite, bentonite, silica, chitin, titanium dioxide, nano clay, nanocellulose, and mixtures thereof. 
     
     
         23 . The method of  claim 14 , wherein the polymer resin further comprises from about 0.5 to about 20 weight percent of at least one nucleating agent selected from the group consisting of polyester waxes, behenamide, crodamide, stearamide, erucamide, pentaerythritol, dipentaerythritol, sulfur and mixtures thereof. 
     
     
         24 . The method of  claim 14 , wherein the polymer resin further comprises from about 1.0 to about 25 weight percent of at least one polysaccharide. 
     
     
         25 . The method of  claim 14 , wherein the polymer resin further comprises from about 0.5 to about 15 weight percent of at least one plasticizer selected from the group consisting of sebacates, citrates, fatty esters of adipic acid, fatty esters of succinic acid, fatty esters of glucaric acid, lactates, alkyl diesters, alkyl methyl esters, dibenzoates, propylene carbonate, caprolactone diols having a weight average molecular weight from about 200 to about 10,000 g/mol, polyethylene glycols having a weight average molecular weight from about 400 to about 10,000 g/mol, esters of vegetable oils, long chain alkyl acids, adipates, glycerol, isosorbide derivatives, and mixtures thereof. 
     
     
         26 . The method of  claim 14 , wherein the polymer resin further comprises from about 15 to about 35 weight percent of at least one filler, from about 1.0 to about 5.0 weight percent of at least one nucleating agent, and from about 0.01 to about 2 of at least one polymerization catalyst or initiator. 
     
     
         27 . A method for making a biodegradable food service item, the method comprising the steps of:
 providing a polymer resin comprising at least 25 weight percent of a first and a second biodegradable polymer;   heating a charge of the polymer resin to a temperature at or above the melting point of the polymer resin; and   molding a food service item from the polymer resin charge.   
     
     
         28 . The method of  claim 27 , wherein the biodegradable food service item comprises an eating utensil, beverage splash stick, cocktail pick, or toothpick. 
     
     
         29 . The method of  claim 27 , wherein the at least one biodegradable polymer in the polymer resin charge comprises a reaction product formed from reactive extrusion of the first and the second biodegradable polymers.